The invention provides water-based ultraviolet dry plastics printing ink, belongs to the field of printing ink, and aims to solve the problem that the ultraviolet cured ink can use water and ethanol as solvents as well as diluents. The water-based ultraviolet dry plastics printing ink comprises the following components in part by weight: 100 to 300 parts of prepolymers, 15 to 50 parts of photoinitiator, 10 to 30 parts of surface active agent, 70 to 150 parts of dye, 60 to 200 parts of water and 40 to 100 parts of ethanol, wherein the prepolymers are water soluble ultraviolet cured resin, such as waterborne epoxy acrylic acid resin, waterborne ultraviolet cured acrylic acid treating polyacrylic acid resin or waterborne polyurethane acrylate. The water-based ultraviolet dry plastics printing ink also comprises one, two or all of three auxiliary agents of a defoaming agent, a flatting agent and a polymerization inhibitor, wherein the average weight parts of the three auxiliary agents are 3 to 17 respectively. The water-based ultraviolet dry plastics printing ink has the advantages of quick drying speed, convenient adjustment of the ink viscosity, simplified dustproof operations, convenient use, good printing quality, easy obtaining of extremely thin ink films, safety, and environmental protection, and can meet the printing activity of plastic printed products.